For a capacitive in-cell touch technology, two layers of strip-like indium tin oxide (ITO) electrodes that overlap each other in different planes are formed in a liquid crystal panel. The two layers of electrodes serve as a touch driving electrode Tx and a touch sensing electrode Rx for a touch panel, respectively, and a sensing capacitor is formed at a position where the two ITO electrodes overlap each other in different planes. An operational procedure of a capacitive in-cell touch panel will be described hereinafter. When a touch scanning signal is applied to the touch driving electrode Tx, a voltage signal generated by the sensing capacitor on the touch sensing electrode Rx is detected. During this procedure, when a body part touches the touch panel, an electric field of the body part will act on the sensing capacitor, so as to change a capacitance value of the sensing capacitor, thereby to change the voltage signal generated on the touch sensing electrode Rx. Then, a position of a touch point may be determined in accordance with the change of the voltage signal.
Currently, the capacitive in-cell touch technology has been applied to an advanced super dimension switch (ADS)-mode liquid crystal panel by some manufacturers. Referring to FIG. 1, which is a schematic view showing an existing ADS-mode capacitive in-cell touch panel, the capacitive in-cell touch panel includes a color filter (Cf) substrate 100, a (thin film transistor (TFT)) array substrate 200, and a liquid crystal layer 300 arranged between the color filter substrate 100 and the array substrate 200. The color filter substrate 100 includes a base substrate 101, a CF functional layer 102 and a touch sensing electrode 103. The array substrate 200 includes a base substrate 201, a TFT functional layer 202 and a common electrode layer 203. The common electrode layer 203 is partitioned into a plurality of touch driving electrodes 2031 and a plurality of common electrodes 2032 arranged alternately, so as to drive the touch driving electrodes 2031 in a time-division manner, thereby to achieve a display function and a touch function. Due to the time-division mode, it is able to reduce the mutual interference between the display and the touch, thereby to improve the display quality and the touch accuracy.
In the above-mentioned in-cell touch panel, the common electrodes are multiplexed as the touch driving electrodes, and meanwhile the common electrode, which is usually made of a transparent metal oxide, e.g., ITO or indium zinc oxide (IZO), has a relatively lame resistance, so signal delay may occur for the touch driving electrode.